How New Mexico Enforces Weight-Distance Tax Compliance

Dec. 3, 2025, 5:03 p.m.
New Mexico is one of a few states that require carriers to pay a weight-distance tax (WDT) based on the weight of a commercial vehicle and the miles it travels in the state. Because this tax is a major revenue source for highway maintenance, New Mexico uses strict enforcement methods to ensure carriers file accurately, pay on time, and operate with proper permits.
New Mexico Weight Distance Tax Compliance

1. Port of Entry (POE) Inspections

New Mexico operates several Ports of Entry where commercial vehicles must stop when entering the state.
At each POE, officers can verify:

  • Valid Weight-Distance Permit or WDT account

  • Quarterly or monthly filing status

  • Payment history

  • Axle weights and registered weight

  • IRP registration and IFTA credentials

  • Trip or temporary permits, if used

If a carrier lacks an active WDT account or permit, officers can deny entry, issue a penalty, or require immediate purchase of a temporary permit.

2. Highway Patrol & Mobile Enforcement Units

New Mexico’s Motor Transportation Police conduct roadside inspections away from Ports of Entry.
They use:

  • Portable scales

  • Automatic license plate readers

  • Compliance databases

  • Inspection histories

Officers compare the vehicle’s declared weight to actual weight and check whether the carrier has been filing and paying WDT properly.
If discrepancies are found, they document violations that may result in:

  • Immediate citations

  • Fines

  • Vehicle being placed out of service until compliance is corrected

3. Weight Sensors & Weigh-In-Motion Systems

Many New Mexico highways include weigh-in-motion (WIM) sensors that measure:

  • Actual vehicle weight

  • Axle configuration

  • Speed and spacing

  • Plate number (via linked cameras)

These systems automatically flag vehicles suspected of weight violations or those operating without a valid WDT permit.
Flags are transmitted to nearby enforcement officers or POEs for further inspection.

4. Tax Filing Audits

The New Mexico Motor Vehicle Division conducts audits to verify whether carriers filed their WDT returns correctly.

Audits often review:

  • Mileage records

  • Trip sheets or ELD data

  • Fuel purchase records

  • Dispatch logs

  • Maintenance and repair documents indicating vehicle operation

  • Weight declarations and axle configurations

If the carrier underreported mileage or weight, the state can issue:

  • Back taxes

  • Interest charges

  • Administrative penalties

  • Suspension of WDT account

5. Electronic Database Cross-Checking

New Mexico integrates multiple compliance systems to track accuracy:

  • IRP and IFTA filings

  • Electronic Logging Device (ELD) data

  • Past WDT filings

  • Temporary trip permit records

  • POE entry logs

  • Highway cameras and WIM sensors

If the mileage reported in WDT filings is inconsistent with what these systems show, the carrier may be flagged for inspection or audit.

6. Penalties for Non-Compliance

New Mexico enforces its weight-distance rules aggressively. Penalties can include:

  • Fines for operating without a permit or underreporting mileage

  • Taxes plus interest for late or inaccurate filings

  • Account suspension until all filings are completed

  • Vehicle impound or out-of-service orders at POEs

  • Denial of future permits until all violations are resolved

Repeat offenders often face higher scrutiny and more frequent inspections.

7. How Carriers Stay Compliant

Carriers can avoid penalties by:

  • Keeping an active Weight-Distance Tax account

  • Filing monthly or quarterly on time

  • Maintaining accurate mileage records

  • Ensuring declared weight is correct for the vehicle

  • Using electronic logs or tracking tools for better accuracy

  • Keeping all documents available for audits

Staying proactive helps carriers move smoothly through New Mexico’s ports and roads without delays or fines.